Predicted to enable cysteine-type endopeptidase inhibitor activity involved in apoptotic process; identical protein binding activity; and signaling receptor binding activity. Acts upstream of or within several processes, including T cell costimulation; positive regulation of T cell chemotaxis; and positive regulation of myoblast fusion. Predicted to be located in plasma membrane. Used to study IgA glomerulonephritis. Orthologous to human TNFSF14 (TNF superfamily member 14). [provided by Alliance of Genome Resources, Apr 2022]